"Kourtney was ready for this baby to come," a longtime family insider confides to OK!. "She and [partner] Scott Disick dreamed about a daughter for so long. They say they really do have everything they want right now, and how happy they are."

Thought they traveled a rocky road during their first years together, Kourtney, 33, and Scott, 29 — already parents to Mason, 2 — are the happiest they have ever been in their relationship.

"Scott really has gone above and beyond," says the family insider. "Throughout this pregnancy, he's been checking in with Kourt a few times every day to make sure that she is okay and asking if she needs anything."

He plans to dote on the baby, too. "A couple of my friends have daughters and say it's the greatest thing because she'll be Daddy's little girl," says Scott, who admits that he always wanted exactly that. "I'm excited to make a little girl's room in the house. I'm excited to buy her little's girl's clothes."